開關(guān)電容儀表的應(yīng)用

　　CMOS模擬集成電路設(shè)計(jì)主要是基于操作電荷。開關(guān)和電容是使用的元素控制和分發(fā)費(fèi)用。整體式過濾器，數(shù)據(jù)轉(zhuǎn)換器和電壓轉(zhuǎn)換器依靠?jī)?yōu)秀CMOS開關(guān)的特性。因?yàn)橹匾栽谒麄兊碾娐烽_關(guān)，CMOS設(shè)計(jì)師發(fā)展的技術(shù)，以盡量減少開關(guān)引起的錯(cuò)誤，特別是那些與雜散電容和開關(guān)時(shí)間。到現(xiàn)在為止，這些技術(shù)已被使用只有在單片器件內(nèi)部結(jié)構(gòu)。一新的設(shè)備，LTC1043，使得這些開關(guān)板級(jí)使用。多極開關(guān)與自驅(qū)動(dòng)，非重疊時(shí)鐘允許在電路中使用的設(shè)備這是不切實(shí)際的與其他開關(guān)。

　　Conceptually， the LTC1043 is simple. Figure 1 details its features. The oscillator， free-running at 200kHz， drives a non-overlapping clock. Placing a capacitor from Pin 16 to ground shifts the oscillator frequency downward to any desired point. The pin may also be driven from an external source， synchronizing the switches to external circuitry. A non-overlapping clock controls both DPDT switch sections. The non-overlapping drive prevents simultaneous conduction in the series connected switch sections.

　　Charge balancing circuitry cancels the effects of stray capacitance. Pins 1 and 10 may be used as guard points for Pins 3 and 12 in particularly sensitive applications